Rotary electric switch



Feb. 20, 1951 A. w. Kali-:GER 2,542,088

ROTARY ELECTRIC SWITCH Filed March lO, 1949 5 Sheets-Sheet l I Isa .5- I8 I6 I9 wf a 2.5 I7 6 2,55

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ROTARY ELECTRIC SWITCH Filed March 10. 1949 5 Sheets-Sheet 2 I 395 C Vm- 54 4a 34g 15J 571C Feb. 20, 1951 A, w, KRlEGER 2,542,088

ROTARY ELECTRIC SWITCH Filed March 10, 1949 5 Sheets-Sheet 3 a sla 6 n 33a 355. Ag'

Feb. 20, 1951 A. w. Kms-GER 2,542,088

ROTARY ELECTRIC SWITCH Filed man 1o, 1949 5 sneets-sneet 4 Feb. 20, 1951 A. w. KRlEGER 2,542,088

ROTARY ELECTRIC SWITCH Filed March 10, 1949 5 Sheets-Sheet 5 A Patented Feb. 20', 1951` ROTARY ELECTRIC SWITCH Alvin W. Krieger, Milwaukee, Wis., assigner t Cutler-Hammer, Inc., Milwaukee, Wis., a corporation of Delaware Application March 10, 1949, Serial No. 80,616

This invention relates to improvements in rotary electric switches.

A primary objective of the invention is Ato improve the construction and the operating characteristics of switches of the aforementioned character.

Another object is to minimize the number of diil'erent parts required to produce a rotary electric switch.

Another object is to provide unusual flexibility in the manner in which the switch parts may be assembled, whereby a large variety of desired circuit controlling characteristics may be attained.

Another object is to provide parts of simple form which may be combined to form switches of either single-pole or multi-pole type.

Another object is to provide novel snap action meafns which permit rotation in either direction selectively.

Another object is to provide combined contact and terminal members of novel form, the terminal portions of which are exposed and readily accessible at the exterior of the switch base.

Another object is to provide a novel form of movable contact carrier.

Another object is to provide an insulating base having recesses of novel form therein to house and support combined stationary contact and terminal members.

Another object is to provide a novel form of insulating base which in cooperation with a contact carrier effectively snuifs out any arcing that may occur at the contacts.

Various other objects and advantages of the invention will hereinafterappear. The accompanying drawings illustrate certain embodiments of the invention which will now be described, it being understood that the embodiments illustrated are susceptible of modification within the scope of the appended claims.

In the drawings,

Figure 1 is a side elevation of a single pole switch (actual size) capable of providing from two to six operative positions.

Fig. 2 is a top plan view of the switch (actual size), the mounting nuts being omitted for sake of clarity.

Fig. 3 is an enlarged vertical section taken on line 3 3 of Fig. 2 with the snap action operating mechanism being shown in elevation and the switch parts in an on position.

Fig. 4 is a-n enlarged vertical section taken on line 4-4 of Fig. 2, but showing the addition of another pole, the contacts of both poles being shown in an off position, the movable contact 14 claims. icl. 20o-ss) of the upper pole being shown in section and that of the lower pole in elevation.

Fig. 5 is a horizontal section taken on line 5-5 of Fig. 4 showing a stop lever in one of its extreme positions.

Fig. 6 is a horizontal section taken on line 6-6 of Fig. 4, the dotted line representation showing a ond position of the switch parts.

g. 7 is a horizontal section taken on line 'l--T of Fig. 4.

Fig. 8 is a horizontal section taken on the broken line 8--8 of Fig. 4 showing two combined stationary contact and terminal members and a movable contact carrier, the full line representation illustrating the switch parts in an oli position, the dotted lines showing the switch parts in an on .position.

Fig. 9 is a horizontal section taken on line 9-9 of Fig. 4 with the contact carrier removed, but with one position of a movable contact illustrated in dotted lines.

Fig. 10 is a horizontal section taken on line lil-I0 of Fig. 4 but with the contact carrier removed and showing two combined stationary contact terminal members and three insulating plugs in position.

Fig. 11 is a detail plan view of a stop lever for a five position switch illustrating its relationship to the operating shaft and stop lug.

Fig. 12 is a horizontal section similar to that of Fig. 9 but showing the contact carrier, additional movable contacts and combined stationary contact terminal members, and a stationary contact ring with an additional terminal lug.

Fig. 13 is a horizontal section similar to that of Fig. 9 illustrating a split stationary contact ring, each segment thereof having a terminal member, the dotted lines representing relative positions of a plurality of movable contacts.

Referring to the accompanying drawings, there is illustrated therein a switch embodying the invention having a maximum of six positions, though it is to be understood that switches having a greater number of positions might be afforded by suitable enlargement of the switch bases. Similarly, while switches having only one and two poles are illustrated, it is to be understood that a greater number of poles may be afforded by addition of extra base sections as will hereinafter appear.

In the drawings the reference numeral l5 designates a preferably cylindrical metal operating shaft for the switch having a flat surface llia at the upper end thereof for accommodating a knob (not shown). As will be apparent the length of 3 shaft I5 will depend on the number of switch poles provided as indicated, for example. by comparison of Figs. 3 and 4. Shaft I5 is rotatably supported by an externally threaded bushing I6 (Fig. 4) having a reduced lower end for insertion through a,

centrally located opening in a substantially circular switch cover member I1. said bushing being upset over the inner surface of said cover member I1 as at I6* to rigidly attach the same thereto. Bushing I6 is further provided with a vertically alined peripheral notch |51 for interlocking with an upstanding lug I1* formed integrally with cover member I1, said interlock preventing relative rotary displacement of the two members. Threaded on to bushing I6 are two nuts I8 and I5, a washer 20, and a locking ring 2| for one-hole mounting of the switch in a well known manner. Shaft I5 is peripherally grooved as at I5b to accommodate a split washer 22 adapted to prevent downward displacement of shaft I5 relative to bushing I6.

As best illustrated in Figs. 5 and 6, the portion of shaft I5 extending immediately downward from the bottom end of bushing I6 is flatted on opposite sides thereof as at I5c for insertion, in the order stated, through correspondingly shaped openings in a stop lever 23 (when employed), an eccentric cam member 24, and a lever member 25 each to be hereinafter more particularly described, said three last mentioned members each being rigidly attached to shaft I5 by staking thereof as at I5e (Fig. 4), the remaining portion I5d of shaft I5 extending downwardly therefrom being of substantially reduced cylindrical contour.

Stop lever 23 may be a flat metal member of peripheral contour best illustrated in Fig. 5 having an arcuate portion 23* the ends of which are adapted to engage a lug I1b formed integrally with and depending from cover member I1, thus to limit the rotation of shaft I5. As will be apparent the permissible degree of rotation of shaft I5, hence the number of operative switch positions, is determined by the degree of arc afforded by said portion 23, that shown in Fig. 5 affording for the switch illustrated three operative positions. It will be obvious to those skilled in the art that omission of stop lever 23 entirely would permit 360 rotation of shaft I5, hence affording in the switch illustrated, six operative positions, while for example, formation of stop lever 23 as shown at |23 in Fig. 1l would afford i'lve operative positions, the relationship of those positions to stop lug I1b being also shown in Fig. 11.

As best shown in Fig. 6, eccentric cam 24 is a flat substantially circular metal member having a peripheral notch 24'* for accommodating the fiatted portion of shaft I5 is hereinbefore described, the center of cam 24 being laterally displaced with reference to the axis of rotation of shaft I5 as will be apparent.

Surrounding cam 24 with a close sliding fit and in the same plane therewith is a flat annular portion 2lia of a lever member 26 adapted to rotate about said cam 24 as a center, said member 26 also having an integrally formed depending portion 26b best illustrated in Figs. 3 and 4.

Lever member 25 (Fig. 6) comprises a flat substantially circular portion 25B rigidly attached to shaft I5 immediately below eccentric cam 24 as hereinbefore described, a wing-like arcuate extension 25b integrally formed with and lying in the same plane as portion 25B, and an integrally formed depending lug 25 best shown in Figs. 3

` center as hereinbefore described.

Slidably fitted about the aforementioned re duced cylindrical portion I5d of shaft I5 (Fig. 4) and extending downwardly from the three afore' mentioned rigidly attached members 23, 24 and 25 substantially the entire length of said portion I5i is a metal bushing 21 preferably square in transverse section. Loosely fitted about the upper end of said bushing 21 is an annular metal bushing 28 having flanges 25'* and 25" at opposite ends thereof to retain in place a relatively heavy helical spring 29 loosely fitted about said bushing 28. Y

As best shown in Fig. 7, a fiat metal member 30 of substantially the contour shown and having a square opening for insertion therethrough of bushing 21 with a close fit and consequent interlocking therewith is mounted to underlie the flanged end 28b of bushing 2B. Said member 35 is slotted at one end thereof as at 30* to slidingly accommodate a lug 26u formed integrally with and extending downwardly from depending portion 2lib of lever 25. As best shown in Figs. 3 and 4, the opposite end of member 35 is provided with an integrally formed upstanding lug portion 3l)b adapted to extend upwardly between bushing 28 and depending lug 25 of lever 25. As best shown in Figs. 3 and 7, the opposite ends 29', 29b of spring 29 are brought out on opposite sides of lugs 25 and 30b thus tending to keep those two members in alinement.

The parts described immediately above when combined with an annular metal stopplate Il to be hereinafter described, form a snap action mechanism adapted to be housed in a substantially circular centrally located recess 32* in a substantially circular molded insulating base section 32 best shown in Figs. 3 and 4, the bottom wall of said recess 32'l having a circular central opening 32b (Figs. 3 and 4) through which shaft portion I5d and its bushing 21 extend with clearance for rotation. Stop plate 3l overlies the top surface of said base section 32, it being interposed between said top surface and a flanged portion I1c of cover member I1. The parts are held in the aforedescribed relation by screws 33 preferably three in number (Figs. 1 and 2) inserted upwardly through alined openings in base sections to -be hereinafter described, base section 32 and stop plate 3|, and threaded into flange portion I1c of cover I1, said screws preferably being upset as at 33a over the top surface of ange I1, the length of said screws, as will be apparent, depending on the number of base sections employed.

As best shown in Fig. 6, annular stop plate 3| is provided on the inner periphery thereof with a series of equally spaced notches 3i* (six in number in the switch illustrated) each being adapted to receive and temporarilyv hold portion 26b of lever 26 against rotary displacement on operation of the snapaction mechanism, the aforedescribed relation affording a switch with a maximum of six operative positions.

The operation of the aforedescribed snap action mechanism is as follows: Assuming the parts to be in the position shown in full lines in Fig. 6, with portion 26b of lever 26 projected into a notch 3l to lock said lever and interconnected member 30 against rotation, clockwise rotation of shaft I5 within the limits afforded by stop plate 23 and stop lug I 1b results in clockwise rotation of lever 25,and its depending lug 25 forcing ond 23 of spring `29 in clockwise direction, the other end of spring 29 being restrained by lugy III"` on locked member 30. Simultaneously eccentric cam 24 is given a clockwise movement about a point defined by the center of shaft I and this rotation of cam 24 results in a gradual movement of portion 26h inwardly toward the center of the switch and out of engagement with the aforementioned notch 3l while lug 26 of depending portion 26 moves inwardly in slot 30 of lever 30. Sufficient clockwise movement of the aforementioned parts havving taken place, portion 26b is moved free oi' the restraining notch 3|, and spring 29 `snaps member 30 rapidly in a clockwise direction and member 30 in turn snaps member 26 in a clockwise direction simultaneously causing bushing 21, to which member 30 is' interlocked as hereinbefore described, to rotate rapidly on portion I5d of shaft I5 as an axis. Continued rotation of lever 26 about cam 24 causes portion 2Bb to be simultaneously moved outwardly to engage the next adjacent notch 3I in stop plate 3l, this preventing any further rotation of the parts. Thus the aforedescribed operation has advanced lever 25 in rotary motion equal to the angular distance of one notch in stop plate 3| (60 in the switch illustrated) to the position indicated by the dotted lines in Fig. 6 and a rapid snap rotary` movement of an equal number of degrees has been imparte to bushing 21. f

As will be apparent, rotation of shaft I5 in a counter-clockwise direction causes the above described parts to respond in a similar manner resulting in snap movement of bushing 21 in counter-clockwise rotation, the aforedescribed operative characteristics thus affording a switch actuating means permitting snap action in either direction of rotation.

As best shown in Figs. 3, 4 and 8, shaft portion I5d and its bushing 21 are inserted with a sliding t through a preferably square centrally located opening (Fig. 8) v in a relatively thick substantially cylindrical body portion 34* of a molded insulating contact carrier 34 to rotatethe same as a function of the snap movements imparted to bushing 21 as hereinbefore described. Said carrier 34 is intermediate the ends of said cylindrical portion 34 and with a plurality (six in the switch illustrated) of substantially rectangular openings 34 extending through said carrier and through both the body portion and c flange Aof said carrier. Openings 34 are equally spaced from and about the center of said contact carrier 34 extending radially beyond the periphery of the body portion 34 into the flange portion 34b asaforeindicated. In any yor al1 of said openings 34 is positioned a U-shaped bridging contactor 35 (Fig. 8). shown in Figs. 3 and 4, each of said bridging contactors hasA its side walls slotted at v35l to provide lateral clearance for and to aid in the positioning of a helical spring 35 located between its side walls. Said springs 36 are placed so that one end thereof abuts the inner end vwall of opening 34, while the other end engages the inner surface of the bottom of U-shaped bridging contactor 35 thus to bias said bridging contactor outwardly so that it projects beyond the periphery Lof cylindrical portion 34 with its ends exposed above and below ilang'e 34h.'

As best provided with a relatively thin integrally formed peripheral flange or lateral extension 34 locatedk each housing comprising matching insulating sections, and the base section 32 forming such'a housing section.

Where a single pole switch is desired (Fig. 3) the base section 32 is utilized as the top of the housing and a bottom section designated generally by the reference numeral 31 is provided. Where a switch of two or more poles is desired (Fig. 4) one or more intermediate base sections designated generally by the numeral 4I), one for each additional pole, may be interposed between said base sections 32 and 31, each such interposed base section to contain a contact carrier of the type above described. The upper surface of each intermediate section 40 may be and preferably is formed substantially identically to the upper surface of bottom section 31, while the bottom surface of each such intermediate base section may be and preferably is formed substantially identically to the bottom surface of base section 32, all as hereinafter more particularly described, thus to provide a structure whereby a varying number of poles may be provided without need of specially designed additional housing parts.

As best illustrated in Figs. 3 and 10, the bottom Asurface of base section 32 is provided with a polygonal central portion 32 extending downwardly a relatively small distance therefrom, said central portion being penetrated by opening 32 for insertion therethrough of shaft portion I5d and its bushing 21 as hereinbefore described. Said central portion 32 is of substantially the same diameter as cylindrical portion 34.of contact carrier 34 and is adapted to function as a bearing surface for the latter. Also the bottom surface of base section 32 is provided with a plurality of integrally formed depending portions 32i and 32 of the contour in horizontal section best 'shown in Fig. 10, said portions 32 being enlarged throughout the depth of said base section 32 and each having an opening for insertion therethrough of one of the screws 33 as hereinbefore described. Portions 32i and 32V are spaced equidistantly about the periphery of the bottom surface of base section 32 to provide a castellated structure (Fig. 1), the inner edges of said portionsv termediate that of the lower surfaces of central v portion 32 and portions 324, 32, said shoulders 32t being adapted to engage flange 34b of contact carrier 34.

The aforedescribed structure provides base 32 with a plurality of peripheral openingsl or windows 'as' illustrated, for example, at 32 (Fig.

10), in each of which may be positioned aU- shaped combined stationary contact and yterminal member 38 (Fig. 3), the number provided varying with the number of operative switch positions desired. As best shown in Fig. 10, said to provide notches to accommodate vextensions As best shown in Figs. 3 and 4; there is provided v a housing for each contact carrier 34 as well as for stationary contacts to be hereinafter described,

32h extending laterally from each of said shoulders 321 thereby to' prevent outward displacementv auaoss members 33 are each preferably provided with a binding screw 33 for attachment of circuit wires; while, as best illustrated in Figs. 3 and 8. the inner arms 38 extend downwardly a distance sufficient to permit them to engage one end of a movable contact 3l hereinbefore described.

In the event that certain of the aforedescribed peripheral openings 32' are unused, a flat insulating member vor plug 39 may be positioned therein to prevent dust or other foreign material from entering the switch. Said insulating members 39 are of suilicient width to close of! the aforementioned openings 32' (Fig. 10) and are adapted to abut the outer side edges of the aforesaid extensions 32h to prevent displacement inwardly, while outward displacement of said insulating members is prevented by an interlock afforded by an upwardly extending tongue 39 (Fig. 3) projecting into a substantially rectangular recess 321 (Figs. 4 and 10) formed in the bottom surface of base section 32 and located with respect to openings 32g as best illustrated in Fig. 10. A second tongue-like extension 33 is provided on the opposite end of member 39 to cooperate in a like manner with a recess 31 in the next adjacent base section as will hereinafter be described.

Base section 31 (Figs. 3 and 4) is of substantially circular contour in horizontal section (Fig. 9) and has a substantially circular centrally located recess 31 (Fig. 3) extending downwardly from the top plane thereof. Extending radially from said central recess 31* are a plurality of smaller recesses 31b (six in number in the switch illustrated) of the contour best illustrated in Fig. 9, the side walls of said recesses being formed by inwardly extending portions 31, 31 formed integrally with the base section 31. Portions 31 and 31 are of the relative size and shape best illustrated in Fig. 9, each having a depressed shoulder 31 of the contour in horizontal section shown in Fig. 9. As illustrated in Fig. 8, said portions 31, 31d may be alined with depending portions 32d, 32 of base section 32 respectively and are adapted to mate therewith thus forming the openings or windows 32 as shown in Fig. l, recesses 31" being alined therewith. As b;st illustrated in Fig. l2, the inner edges of said portions 31, 31 are so spaced from the center of the base as to provide clearance for the flange 34 of contact carrier 3l when in assembled relation, while, as best illustrated in Fig. 3, the upper surfaces of shoulders 31 are adapted to cooperate with shoulders 32t depending from base section 32 to form a guideway for said flange portion 34, and the inner edges of said portions 31 are so spaced from the center of base section 31 as to provide clearance for cylindrical body portion 34 of contact carrier 3|.

The bottom wall of recess 31 may be provided with a centrally located substantially circular portion 31 (Fig. 9) formed integrally therewith and extending upwardly therefrom. As best illustrated in Figs. 3 and 4, said portion 3'Ix is adapted to provide a bearing surface for cylindrical body portion 34* of contact carrier 34 and the lower end of bushing 21, a centrally located opening 31l being provided for insertion therethrough with a sliding fit of the lower end of shaft portion i".

A flat annular metal collector ring 4| (Fig. 9) of good electrical conductivity is provided for positioning within recess 31 against the bottom 8 tion 31'. The outer periphery of said collector ring 4| is provided with a plurality of equally spaced integrally formed upturned portions Il (Fig. 3) to serve as stationary contacts as will hereinafter be described, said portions Il' projecting radially a sufficient distance into recesses 31h (Fig. 9) to cause the side edges thereof to interlcok with the side edges of shoulders 31, thus to prevent rotary displacement of said collector ring 4|. In lieu of a stationary contact member II, collector ring Il is provided at one point on the periphery thereof with an integrally formed upturned terminal member 4Ih (Fig. 9) extending outwardly into recess 31 and upwardly (Fig. 4) a sufficient distance to permit a binding screw 4I threaded therein to project outwardly for access from the exterior of the switch through window or opening 32l hereinbefore described. As best shown in Figs. 4 and 8, the terminal screw portion I Il of said terminal member lib is of suicient size to close oil window 32', the side edges of said portion 4 Id overlapping the top surface of base section 31 while the inner surface of said portion abuts the side edges of portions 32h of base section 32. The upper end of said portion Ild is also provided with an upwardly extending tongue 4i (Fig. 9) for insertion into recess 32l of base section 32, (Fig. 4),

l rec tion.

An annular insulating washer I2 surrounding portion 31 of base' 31 may be interposed between collector ring 4| and contact carrier 3l asshowninFigs. 3 and 4.

As illustrated in Fig. 3, stationary contact portions ll are each positioned in alinement and in spaced opposed relation to inner arms 33 of such combined stationary contact and terminal members 33 as may be employed, the outer arms 33 of each of said U-shaped members 38 having a depending tongue portion 33 (Fig. 10) extending downwardly into recesses 31h for interlocking with base section 31 (Fig. 3) to aid in maintaining such positioning and spacing when the aforementioned parts are in assembled relation. Said stationary contacts 33 and lil are adapted to be bridged by contactor 35 when contact carrier 3l is in one ofthe operative switch positions as illustrated, for example, in Fig. 3, springs 33 maintaining a sufficient contact pressure between contacter 3l and the pair of stationary contacts 33, Ill bridged by it. In this position a path of electrical conductivity is established from terminal member Il through collector ring 4I, stationary contact 4I, bridging contactor 3l, stationary contact 33gto terminal portion 3l".

As will be apparent, rotary movement of coritact carrier 3l as a function of movement of the snap action mechanism hereinbefore described from one operative switch position to the next, moves bridging contactor 3l rapidly out of engagement with stationary contacts 33 and lil, the circuit therefore being broken at two points, which feature together with the snap movement heretofore described tends to minimize arcing of the contacts. This tendency to minimize arcing is further aided by virtue of the relationship of contact carrier 34 with mating shoulders 32t and 31 on base sections 32 and 31 respectively; this relation being such that as bridging contactor 3l reaches a point midway between any two operative switch positions it wall thereof and fitted around said circular porn is substantially isolated by insulation material from any current carrying parts, the .adjacent portions `,of cylindrical portion 34l of contact carrier 34 having rotated to meet shoulders 321 and 31' and ange portion 34* having similarly rotated in its guideway formed by the top and bottom surfaces of said shoulders 31 and 3'|t respectively. Thus any arc which may have developed between bridging contactor 35 and either of the stationary contacts 4|* or 3|!b is effectively cut ofi. I

As will be apparent from inspection of Fig; 4, when bridging contactor 35 is in the operative switch position illustrated therein i. e. opposite terminal member 4| b, no electrical connection isy made, thereby providing the switch with an oil position if desired.

It will be obvious to those skilled in the art that in addition to the various commutation characteristics aorded by the ilexibility of the number of operative switch positions and/or the number of poles provided as hereinbefore described, additionali commutation combinations may be attained by provision of one or more additional combined stationary contact and terminal members 3B and/or addition of one or more additional contactors 35 in openings 34 in contact carrier 34, as shown, for example, in Fig. 12, wherein is illustrated aswitch having four combined contact and terminal members 38 and three contactors 35,'it being obvious to those skilled in the art that said contactors 35 might be spaced in other arrangements than that illustrated. y

Fig. 12 additionally illustrates a further variation in that collector ring 4| is shown with an additional terminal member 4|b. A still further commutation characteristic may be provided by breaking collector ring 4| into two or more segments as illustrated, for example, at |4|, |4|b in Fig. 13, each segment being provided with a terminal member 4|". From' the foregoing, it willbe apparent that the invention embodied by the drawings provides a multitude of circuit commutation combinations which may be achieved by a minimum of simple parts which are yeasily and quickly interchanged, thereby aiording a switch of great exibility.

I claim:

1. In a rotary switch, a substantially cylindrical insulating contact carrier rotatable on its central axis, an insulating base for said contact carrier, 'saidl base having walls to form about said contact carrier a plurality of chambers, and

cooperating switch contacts comprising a contactor on said carrier and vcontacts mounted in pairs in said chambers, said carrier having its contactor peripherally mounted thereon and l` having a peripheral flange projecting from a midpoint of said contactor, said chambers' being formed to receive therein with a rotating clearance said flange and having 'their respective contacts disposed on 'opposite -sides of said flange to be engaged by the' portions of said contactor on opposite sides of saidiiange, said base and 6'5 to minimize persistence of any arcing as said said insulating contact carrier being close fitting contactor `leaves any of said chambers;

2. In a-rotary switch, `a'sub'santially cylindriformed to receive therein with a rotating clearance said fiange and having their respective contacts kdisposed on opposite sides of said flange to be engaged by the portions of said contactor on opposite sides of said ange, said base and said l0 insulating contact carrier being closefitting to minimize persistence of any arcing as said contactor leaves any of said chambers.

3. In a rotary electric switch, an actuating mechanism having a rotary actuated part, a substantially cylindrical insulating contact carrier rotatable on its central axisv by said actuated part of said actuating mechanism, an insulating base supporting in coacting relation said mechanism and contact carrier, said base having walls forming about said contact carrier peripherally thereof a plurality of chambers, and cooperating switch contacts comprising at least one spring biased contactor on said carrier and contacts mounted in pairs in said chambers, said carrier 26 having a plurality of peripheral recesses equally spaced from and about its center each for removable mounting therein of one such contactor in a parallel relation to its axis of rotation and said carrier having an encircling peripheral flange 30 projecting from a midpoint of said contactor,

said chambers being formed to receive therein with a rotating clearance said ilange and having their respective contacts disposed on opposite sides of said ange to be engaged by the portions of said contactor on opposite sides of said ilange,

said base and said insulating contact `carrier being close' fitting to minimize persistence of any arc as said contactor leaves any of said chambers.

40 4. In a rotary electric switch, a snap acting actuating mechanism having a rotary actuated part, a substantially cylindrical insulating contact carrier rotatable on its central axis by said actuated part of said actuating mechanism, an

insulating base supporting in coacting relation said mechanism and contact carrier, said base having walls forming about said contact carrier peripherally thereofa plurality of chambers each beingopen adjacent said carrier, and cooperating 5 switch contacts comprising a contactor on said carrier and contacts mounted in pairs in said chambers, said carrier having its contactor mounted peripherally thereon in a parallel relation to its axis of rotation and having a peripheral flange projecting from a midpoint of said contactor, said chambers being formed to receive therein with a rotating clearance said flange and having their respective contacts disposed on Iopposite sides of said ange t'o be engaged by the *6 portions of said contactor on opposite sides of said flange, one of eachfof' said pairs of contacts comprising an `upturned edge oi a collector ring havingat least one terminal portion'.

5. In a rotary electric switch, a snap acting actuating mechanismhaving a rotary actuated part, a` substantially cylindrical insulating contact carrier rotatable on .its central axis by said actuated part of .saidractuating mechanism, said carrier having a contactor mounted peripherally 7 thereon in a parallel relation to its axis of rotation and .having a peripheral .flange projecting laterally from a midpoint of said contactor, an

insulating base supporting incoactingv relation said mechanismand contact carrier, said base comprising a pair ofv base sections having walls adapted to mate on a plane extending through said flange at a right angle to the central axis of said carrier, said base sections jointly forming an enclosure for said carrier and jointly forming peripherally thereof a plurality oi' chambers adapted to receive therein with a rotating clearance said flange, and a pair of contacts mounted in said chambers on opposite sides of said flange to be engaged by the portions of said contactor on opposite sides of said ilange, said base and said insulating contact carrier being close fitting to minimize persistence of any arcing as said contactor leaves any of said chambers. 4

6. In a rotary electric switch. a snap acting actuating mechanism having a rotary actuated part, a substantially cylindrical insulating contact carrier rotatable on its central axis by said actuated part of said actuating mechanism, said carrier having a contactar mounted peripherally thereon in a parallel relationto its axis of rotation and having a peripheral iiange projecting laterally from a VVmidpoint of said contactor, a ilrst insulating base section supporting said mechanism, a second base section adapted to mate with the first transversely ofv the axis of said carrier to house said carrier removably, said base sections. having walls jointly forming peripherally oi' said carrier a plurality of chambers adapted to receive therein with a rotating clearance said ilange, a pair of contacts mounted in one o! said chambers on opposite sides oi saidiiange to be engaged by the portions of said oontactor on opposite sides of said flange, and a third base section adapted to be interposed be- 3 tween and to mate with said iirst and second base sections to provide separate housings, each of the character aforestated, for two o! said carriers and their cooperating contacts.

7. In a rotary electric switch, an actuating i mechanism having a rotary actuated part, a plucarriers and having recessed mating walls jointly forming about the respective contact carrier peripherally thereof a plurality of chambers adapted 55 to receive therein with a rotating clearance the nange of the carrier, and contacts mounted in pairs in at least some oi' said chambers, the

contacts of each pair being spaced to receive therebetween the carrier ange accommodated by the respective chamber and being engageable for bridging by a contactor oi' the respective carrier.

8. In a rotary electric switch, actuating mechanism having a rotary actuated part. a plu' relation said mechanism and contact carriers and 'l5 s forming about the respective contact carrier peripherally thereof a plurality of chambers adapted to receive therein with a rotating lclearance the ange oi the carrier. and contacts mounted in pairs in at least some o! said chambers, the con- 10 tacts of each pair being spaced to receive therebetween the carrier iiange accommodated by the respective chamber and being engageable for bridging by a contactor of the respective carrier, said contact carriers being interchangeable in 5 respect oi' the base sections.

9. In a rotary electric switch, an actuating mechanism having a rotary actuated part, a plurality of substantially cylindrical contact carriers rotatable on a common central axis by` said Aactuated part of said actuating mechanism, each of said carriers having a contactor mounted peripherally therein in a parallel relation to its axis of rotation and having a peripheral iianse DTO- 1 jecting laterally from a midpoint o( said con- *5 tactor, an insulating base supporting in coacting relation said mechanism and contact carriers and being divided transversely of the axis ot said carriers into`a plurality of sections, each two adjacent sections housing removably one of said carriers and having recessed mating walls jointly iormingabout the respective contact carrier peripherally thereof a plurality of chambers adapted to receive therein with a rotating clearance the iiange of the carrier, and contacts mounted in pairs in at least some oi' said chambers, the contacts of each pair being spaced to receive therebetween the carrier ange accommodated by the respective chamber and being engageable for o bridging by a contacter of the respective carrier,

said contact carriers being interchangeable in re spect of the base sections, and each intermediate base section having one side adapted to mate with one end base section and its other side adapted to mate with the other end base section to form with either end base section a carrier housing of the character aforestated.

l0. In a rotary electric switch. an actuating mechanism having a rotary actuated part, a substantially cylindrical insulating contact carrier concentrically mounted on said actuated part, said carrier having an integral relatively thin centrally positioned insulating flange laterally #extending from its outer periphery, a bridging contactor resiliently mounted in said carrier adjacent said flange in parallel relation to its axis of rotation and being limited in outward radial displacement thereby, said contactor having contact portions extending above and below said flange. an insulating housing having interior portions which cooperate with said ilange to provide a plurality of substantially isolated individual upper and lower contact chambers positioned along the outer periphery of said carrier and pairs of stationary contacts contained in at least 5 some of said upper and lower chambers for bridging engagement by said bridging contacter. whereby the arcing occurring between pairs of enssins contacts is substantially isolated for rapid extinguishment when said contactor is moved out oi' engagement therewith.

recess in its periphery extending parallel to said axis, a relatively thin integral peripheral insulating ilange extending across the middle portion oi' said recess, a contactor removably mounted in said carrier recess with its contact portions exposed on opposite sides of said flange for tangential engagement with stationary contacts, said contactor also being limited in outward radial displacement by said iiange, and a spring positioned within said recess and engaging said contactor to bias the latter outwardly into abutting relationship with said ange.

12. As an article of manufacture, a. unitary molded insulating contactor carrier comprising a cylindrical body portion for rotation about its axis, said body portion having a plurality of individual contactor receiving recesses in its outer peri-phery, said recesses extending in a plane parallel to said axis, and an integral relatively thin substantially circular flange on the periphery of said body portion intermediate the ends thereof, said ilange having notches in its inner periphery opposite said contactor receiving recesses whereby contactors located within said recesses may project radially outward a predetermined distance.

13. As an article of manufacture, a bridging contactor assembly, for use in an insulating contact carrier of the type wherein the contactor is resiliently retained within a recess and is limited in outward movement by an insulating ilange extending across the face of said recess. comprising 14 a metal member of U-shape in transverse cross section and of good electrical conductivity, said metal member having a front contact portion and -parallel side portions, said side portions having alined notches extending throughout the depth of the former intermediate the ends thereof. and a coiled compression spring of a diameter to afford a snug t thereof between the innermost edges of the walls of said notches, whereby said spring is restrained against lateral displacement in any direction relatively to said contactor. 14. A contactor assembly as in claim 13, wherein the diameter of the spring is no greater than the overall width of the metal member.

ALVIN W. KRIEGER.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS Number Name Date 582,114 Davis May 4, 1897 616,405 Clark Dec. 20, 1898 646,146 Hart Mar. 27, 1900 1,561,640 Eyrand Nov. 17, 1925 1,864,532 Forss June 28, 1932 1,905,689 De Reamer Apr. 25, 1933 2,273,417 Parker Feb. 17, 1942 

